1. Field of the Invention
The present invention relates to a recording and reproduction apparatus which records and/or reproduces AV (audio visual) data, and to a medium and an information assembly.
2. Related Art of the Invention
In recent years, together with the spread and progress of personal computers, disk apparatuses, such as a magnetic disk apparatus, have been used as an external memory apparatus in a great number because of their large capacitance and high speed. Together with the significant expansion of computer software and the great increase of the capacitance for the handled data, these disk apparatuses used as the external memory apparatus have rapidly improved in areas of performance such as memory capacitance and processing speed.
By making good use of their high speed and their large capacitance disk apparatuses are being used not only in computers but also in digital AV equipment for recording and reproducing images and sound by applying digital technology.
In this manner, in an image and sound recording and reproduction apparatus, such as a magnetic disk apparatus, wherein AV data are recorded and reproduced by utilizing a disk medium, an Audio/Video Control (AV/C) command set is conventionally used at the time when AV data are recorded or reproduced. Here, the AV/C command set means an AV/C digital interface command set.
According to the AV/C command set, the AV data recorded in the disk medium are not directly accessed or a command for directly accessing management information which manages the AV data recorded in the disk medium is not supported. That is to say, recording or reproduction of AV data to or from the disk medium are controlled by a recording start command, a reproduction start command, a recording and reproduction stop command, and the like, and these commands are issued by designating the identification numbers of the AV data. Thus, the management information is managed by a controller inside of the image and sound recording and reproduction apparatus and, therefore, cannot be directly accessed from external equipment. In this manner, the image and sound recording and reproduction apparatus records or reproduces AV data by means of non-raw access commands such as an AV/C command set.
On the other hand, it is possible to connect the image and sound recording and reproduction apparatus to a personal computer. In the case that the personal computer accesses the disk medium, data are conventionally written in or read out by designating an LBA (logical block address) . In the case that the image and sound recording and reproduction apparatus is connected to a personal computer in the above described manner, it would be advantageous if raw access commands could be utilized which carries out write in or read out of data on the disk medium by designating the LBA. In this case, the personal computer could directly access management information which controls the AV data concerning the disk medium or the AV data stored in the disk medium.
In the case that the image and sound recording and reproduction apparatus is not only connected to AV equipment but also can be connected to a personal computer, not only are AV data recorded and reproduced but also the AV data stored in the disk medium can be edited and processed by using the personal computer.
In this manner, by supporting not only a non-raw access command but also raw access commands, the image and sound recording and reproduction apparatus is not only connected to AV equipment but also is connected to a personal computer, plenty of functions such as recording, reproducing, editing and processing, and the like, can be provided.
In the case that a recording and reproduction apparatus such as an image and sound recording and reproduction apparatus is made to be connectable to a personal computer and AV equipment, however, the personal computer directly accesses the disk medium by designating an LBA, that it to say, it accesses the disk medium by using raw access commands and therefore, there is a possibility that the AV data recorded in a disk medium or the management information may be destroyed by mistake. In the case that such an event occurs, the image and sound recording and reproduction apparatus cannot carry out recording and reproduction of AV data.
That is to say, in the case that equipment for supporting raw access commands can be connected to a recording and reproduction apparatus, the problem arises that there is a possibility wherein the equipment for supporting the raw access commands mistakenly destroys either the AV data recorded in the disk medium or the management information for managing AV data.